JP6296165B2 - Method for transmitting data between a user equipment and a base station in a wireless network - Google Patents

Description

  The present invention relates to a method for transmitting data between a user equipment and a base station in a wireless network. In particular, the present invention is for transmitting data between a base station comprising a plurality of antennas and user equipment for transmitting radio frequency signals according to so-called multi-input multi-output (MIMO) technology or so-called diversity mode. Regarding the method. The invention further relates to a base station and user equipment for performing the method.

  To increase the performance and reliability of data transmission, so-called multi-input multi-output (MIMO) technology may be used to transmit information between the base station and the user equipment in radio frequency communication. MIMO technology relates to the use of multiple transmit and receive antennas for wireless communication in a base station and / or user equipment. MIMO technology forms the basis of an encoding method that uses the time dimension as well as the space dimension to transmit information, thus allowing for space and time encoding. Therefore, there is a possibility of increasing the quality and data rate of wireless communication.

  In so-called massive MIMO systems, multiple user equipments may be located in a cell served by a base station having multiple antennas. In a massive MIMO system, the configuration of each antenna transceiver of the base station may vary depending on the respective location of the user equipment and transmission conditions in the base station and user equipment environment.

  A massive MIMO system may be used in connection with a time division duplex (TDD) system where transmission of an information stream between a base station and user equipment is divided into time slots. Different time slots for uplink (UL) data communication and for downlink (DL) data communication transmit information from user equipment to base station and from base station to user equipment May be provided. In a massive MIMO system, an additional time slot that may be referred to as a “header” for transmitting a training signal or training sequence from the user equipment to the base station is required. Based on the received training signal, the base station may configure a transceiver for the base station antenna array. Thus, a high antenna gain for the payload transmitted in subsequent time slots is achieved. The payload may be transmitted in several uplink and downlink time slots. However, when the user equipment is moving, the channel quality can degrade due to changes in the spatial arrangement of the base stations and / or user equipment. Accordingly, further training signals may be transmitted and the transceiver configuration may be updated.

  Generally, a massive MIMO system is assumed to be in a building such as an office or a shopping mall. In this environment, there is a possibility that many user devices exist. However, high data throughput and high data reliability are achieved in this environment using MIMO technology by spatial coding with individual configuration of antenna parameters for each user equipment. For further improvement, so-called 3D-MIMO systems are used in which multiple base stations, each having multiple antennas, work together to enable more enhanced spatial coding of transmitted information. .

  Many user equipments, such as handsets such as mobile phones, provide two or more antennas for cellular communications. User equipment antennas are typically placed at or apart from the housing of the user equipment, such as one antenna at the top of the user equipment and one antenna at the bottom of the user equipment. . The two antennas may be used in two different modes for downlink (DL) communication, such as either diversity mode or MIMO mode. In the diversity mode, the base station transmits a single radio frequency signal and both antennas receive it. If a situation occurs where one of the multiple antennas is in the fading dip, or if the user is covering one antenna, the other antennas may still have a connection with the base station and reception may continue. . Diversity mode is also called rank 1 mode. In diversity mode, the second antenna may be considered as a backup antenna. In the MIMO mode, also called rank-2 mode, the base station transmits two different spatially encoded signals on the exact same frequency channel. Therefore, the data rate may be improved by a factor of two. Two different radio frequency signals may be received by two spatially separated antennas of the user equipment. Beamforming or radio frequency signal focusing may be such that one of two such different signals may be received by the first antenna of the two antennas of the user equipment, the other of the two different signals being two of the user equipment. It may be achieved by multiple antennas of the base station, or by the base station operating according to the massive MIMO or 3D-MIMO techniques described above, as may be received simultaneously by the other of the antennas. As mentioned above, in a scattered situation or scenario with many user equipments, predict how to supply all the antennas of the base station to provide the necessary radio frequency energy focusing I can't. Thus, each user equipment needs to transmit a training sequence and, for example, the amplitude and phase for each of the base station antennas are transmitted by focusing the radio frequency signal on the antenna of the user equipment where the training sequence is transmitted. May be determined.

  Configuration parameters for downlink communication may be obtained based on training sequences received on the uplink based on channel correlation. In scenarios where there is an increase in transmission frequency, a lot of reflections, such as an indoor office, and no line-of-sight (LOS), the focusing becomes very narrow and is actually one of the user equipment antennas. Narrow enough to cover. For example, focusing may be only one tenth of the wavelength of the transmission frequency. Thus, for each antenna that needs to be covered by the beam formed by the base station, a training sequence may need to be transmitted, and thus a transmitter is required for each user equipment antenna. However, in a typical user equipment with two antennas, there may be only one transmitter for cost optimization, while in order to enable the diversity mode described above, usually two A receiver is assumed. Therefore, there is a need for a method that enables data transmission between a user equipment and a base station according to the above-described MIMO technology without increasing the complexity and cost of the user equipment in a massive MIMO or 3D-MIMO system. .

  According to the invention, the subject matter is a method for transmitting data between a user equipment and a base station in a wireless network according to claim 1, a base station of a wireless network according to claim 11, claim 13. A wireless network user equipment according to claim 16 and a method for transmitting data between a user equipment and a base station in a wireless network according to claim 16. The dependent claims define preferred and advantageous embodiments of the invention.

  According to an aspect of the present invention, a method is provided for transmitting data between a user equipment and a base station in a wireless network. The user equipment includes at least a first antenna and a second antenna for transmitting a radio frequency signal between the user equipment and the base station. User equipment may have more than one antenna, in which case the described method may be adapted in response to using more than one antenna. However, even if the user equipment has more than one antenna, the described method may also be performed using only two antennas. The base station includes a plurality of antennas for transmitting radio frequency signals between the base station and user equipment. The terms used herein, such as “transmit”, “transmit”, may relate to the reception at the base station of information from the user equipment, as well as the transmission of information from the base station to the user equipment. Data transmitted from the base station to the user equipment may be referred to as downlink (DL) data or data transmitted in the downlink direction, and data transmitted from the user equipment to the base station may also be uplink ( (UL) data or data transmitted in the uplink direction. According to the method, a first training signal is transmitted from a user equipment to a base station via a first antenna of the user equipment in a first period. For each antenna in the subset of antennas of the base station, a corresponding first configuration parameter is determined based on the first training signal received at the corresponding antenna. Further, a second training signal is transmitted from the user equipment to the base station via the second antenna of the user equipment in the second period. The second period is different from the first period. For example, in the time division multiplex transmission method, the first period may include the first time slot, and the second period may include the second time slot. Good. For each antenna in the subset of antennas of the base station, a corresponding second configuration parameter is determined based on a second training signal received at the corresponding antenna. The first and second configuration parameters may be used to transmit a payload information block between the base station and the user equipment. The subset of antennas may include those antennas of the plurality of antennas configured to receive first and second training signals from the user equipment. For example, if the base station antennas are arranged in a cylindrical shape, only a subset of the antennas may receive training signals transmitted from the user equipment and some other antennas will not receive training signals. May be. Furthermore, if a very large antenna array is used, only a part or a subset of the antenna array may be used for a particular user equipment. However, the subset may include all of the multiple antennas provided by the base station. As an example, a base station may include, for example, 30 to 100 antenna arrays, or may include more antennas arranged in, for example, a matrix or a cylinder. Similarly, user equipment may include more than one antenna, for example, three or four antennas. If the user equipment comprises more than one antenna, the described method may be adapted according to multiple antennas. Due to the configuration parameters determined for each antenna of the subset of multiple antennas, the base station can communicate with each antenna of the user equipment according to the MIMO technique described above. Thus, according to this method, the first downlink data is transmitted from the base station to the user equipment using the first configuration parameter determined for the antenna of the base station, and at the same time the second downlink data Data is transmitted from the base station to the user equipment using the second configuration parameter determined for the base station antenna. The first and second downlink data may be transmitted on the same frequency. By using a first configuration parameter to transmit first downlink data and by using a second configuration parameter to transmit second downlink data, the first downlink Spatial coding is provided so that data can be received with high quality at the first antenna of the user equipment and second downlink data can be received with high quality at the second antenna of the user equipment. Although the first and second downlink data may be transmitted simultaneously. Leakage between user equipment antennas may be handled by encoding so that the user equipment can separate the first and second data.

  In diversity mode, the first downlink data may include the same data as the second downlink data, and for processing depending on which downlink data provides better reception quality, the user equipment One of the downlink data and the second downlink data may be selected. Additionally or alternatively, both first and second downlink data signals may be received and combined to provide downlink data for further processing. Thus, in diversity mode, for example, if one or both user equipment antennas are covered or have degraded reception quality, for example, the user may grip the user equipment and thus interfere with reception at the antenna. Even high transmission quality and reliability are provided. In MIMO mode, the first downlink data may be different from the second downlink data, and both data may be processed at the user equipment after reception. Thus, in MIMO mode, higher data rates may be achieved, for example up to twice as high via two antennas.

  According to this method, a first signal quality parameter of first downlink data received at a user equipment is determined, and a second signal quality parameter of second downlink data received at a user equipment is determined. Is done. Based on the determined first quality parameter and second quality parameter, one of the first and second antennas of the user equipment is configured to transmit uplink data from the user equipment to the base station. Selected. In other words, according to the above method, the configuration parameters that are accurately adapted to the antenna of the base station in order that the downlink communication supporting either the MIMO mode or the diversity mode concentrates on the multiple antennas of the user equipment. It becomes possible using. Further, selection diversity or switching diversity may be realized in the uplink direction. Uplink communication from either one of the user equipment antennas is provided with high quality by appropriate configuration of the base station antennas. Also, the above method may be implemented with a single transmitter or transmission unit at the user equipment, since the first training signal and the second training signal are transmitted in separate periods. Therefore, the above method may be realized at low cost in the design of the user equipment of the present embodiment.

  According to an embodiment, the step of selecting the antenna of the user equipment for transmitting uplink data is performed by the user equipment. The base station may listen on both channels of uplink data coming from the first antenna or the second antenna of the user equipment. However, only uplink data from either the first antenna or the second antenna exists. Thus, the base station receives only uplink data on one channel. Such a configuration where the base station is not involved or not notified about antenna selection for uplink data may be referred to as open loop antenna selection. Additional protocol elements and protocol overhead for synchronizing user equipment and base stations are not required.

  According to another embodiment, the antenna selection of the first and second antennas of the user equipment for uplink data transmission is performed by the user equipment, and the selected antenna is notified from the user equipment to the base station. . As mentioned above, the base station is not involved in the selection process and thus represents an open loop process in this embodiment. However, reception of uplink data may be more efficiently realized in the base station by notifying the base station of the selection result.

  According to a further embodiment, for user equipment antenna selection for uplink data transmission, based on the determined first and second signal quality parameters, the user equipment second for uplink data transmission A suitable antenna of the first and second antennas may be selected by the user equipment. The preferred antenna may be signaled from the user equipment to the base station, and the base station is the base station that the preferred antenna of the user equipment is selected for the transmission of uplink data from the user equipment to the base station. A response that is expected to be used may be sent to the user equipment. That is, the user equipment requests permission at the base station to select an antenna to be used for uplink data transmission. Upon response from the base station, the user equipment may use the selected antenna. Thus, a closed communication loop is provided and both the base station and the user equipment are involved in the selection process.

  According to yet another embodiment, the first and second signal quality parameters are transmitted from the user equipment to the base station. At the base station, the antennas of the first and second antennas of the user equipment are selected based on the first and second signal quality parameters. The selected antenna is notified from the base station to the user equipment. That is, the base station controls which antenna of the user equipment is used. This allows the base station to select an antenna in view of further other situations in the cell provided by the base station, such as communication channels for other user equipment in the cell.

  According to another embodiment, the user equipment includes a transmission unit and a switch configured to selectively connect either the first antenna or the second antenna to the transmission unit. In this case, the user equipment may have two or more antennas, and the switch may be configured to selectively connect the transmission unit to one of the two or more antennas. Also, the user equipment may include a plurality of transmission units, but there are fewer transmission units than antennas. In this case, the switch may be configured to selectively connect each of the antennas to at least one transmission unit such that each antenna is connected to the transmission unit in a time multiplexing scheme. However, this also means that not all antennas can be connected to the corresponding transmitting unit at the same time. According to this embodiment, in order to transmit a first training signal from the user equipment to the base station, the transmission unit is connected to the first antenna via the switch in the first period. And in the second period, the transmission unit is connected to the second antenna via a switch for transmitting the second training signal. By connecting the transmission unit to the first and second antennas in time multiplexing, or by connecting the plurality of transmission units to multiple antennas of the user equipment in time multiplexing, a smaller number of antennas A transmission unit is required to achieve the method described above. In particular, one transmission unit may be required to provide first and second antennas for transmitting corresponding training signals, as well as more antennas.

  The first and second quality parameters may each include, for example, a corresponding downlink data bit error rate, a corresponding downlink data received signal strength indication, or a corresponding downlink data signal-to-noise ratio, respectively. The quality parameters described above can be easily determined within the user equipment and provide reliable information regarding the transmission quality of the downlink data. Also, the quality parameters described above may be transmitted to the base station in a corresponding protocol data unit in a generally known manner for the processing described above in the base station.

  According to an embodiment, the configuration parameters determined for each antenna of the subset of the plurality of antennas of the base station include a pair of parameters including, for example, amplitude information, phase information, and phase information associated with the amplitude information. A plurality of these parameters, or signal strength information of the signal strength received at the corresponding antenna when the corresponding training signal is received. However, the configuration parameters listed above are merely examples, and the configuration parameters include other or additional information for configuring the base station antenna to enable data transmission according to the MIMO transmission scheme described above. But you can. Also, the phase and amplitude information is used directly to determine the configuration parameters of the base station antenna for receiving uplink data from the user equipment when the training sequence is transmitted in the same uplink direction. Also good. However, the configuration parameter for transmitting downlink data to the user equipment may be determined based on a Hermitian transposition of the configuration parameter for receiving uplink data. For example, if two uplink signal beams from user equipment are received at the base station with different delays (phases), the phase needs to be inverted in order to transmit the downlink beam as a beam with a short incoming path first And both beams need to be adjusted at the user equipment in the downlink direction.

  According to another aspect of the present invention, a base station of a wireless network is provided. A base station transmits a radio frequency signal between a user equipment having at least a first antenna and a second antenna for transmitting a radio frequency signal between the user equipment and the base station, and the base station. A plurality of antennas. The base station further comprises a processing device configured to receive a first training signal transmitted from the user equipment to the base station via the first antenna in the first period. The processing device is configured to determine a corresponding first configuration parameter for each antenna of the subset of antennas of the base station based on a first training signal received at the corresponding antenna. . The processing device is configured to receive a second training signal transmitted from the user equipment to the base station via the second antenna in the second period. The first period and the second period may be different, for example, the second period occurs after the first period. The processing apparatus determines a corresponding second configuration parameter for each antenna of the subset of the plurality of antennas of the base station based on the second training signal received by the corresponding antenna. Then, the first and second downlink data are simultaneously transmitted from the base station to the user equipment, that is, the transmission of the first downlink data and the transmission of the second downlink data have at least overlap. The first downlink data is transmitted using a first configuration parameter determined for the base station antenna. The second downlink data is transmitted using the second configuration parameter determined for the base station antenna. By using the first and second configuration parameters to transmit the first and second downlink data, the first downlink data is received with high quality at the first antenna of the user equipment, and the second Spatial encoding of the first and second downlink data is provided so that the downlink data is received with high quality at the second antenna of the user equipment. Signal processing (eg, via MIMO technology) for transmitting the first and second downlink data using the first and second configuration data may be performed in the analog or digital domain or a combination thereof. . Thus, for example, in a signal processing or processing device, some of the transmit / receive functions of each antenna may be implemented digitally, and the remaining portions of the antenna and transceiver may be passive components. If the user equipment is operating in diversity mode, the first and second downlink data may include the same data, while if the user equipment is operating in MIMO mode, the first and second The downlink data may contain different data, so the data rate is increased up to a factor of 2, for example. Further, the processing device is configured to receive uplink data transmitted from the user equipment via either the first antenna or the second antenna. In order to receive uplink data transmitted via the first antenna, the processing device uses the first configuration parameter and receives uplink data transmitted via the second antenna of the user equipment. To do so, the processing device uses a second configuration parameter. However, the base station may uplink in both cases, i.e. when the user equipment transmits uplink data via the first antenna, or when the user equipment transmits uplink data via the second antenna. Like the first configuration parameter, the second configuration parameter may be used simultaneously to listen for uplink data so that data can be received.

  According to certain embodiments, the base station is further configured to perform any of the methods and embodiments described above, and thus includes the advantages described above.

  According to another aspect of the invention, a user equipment for a wireless network is provided. The user equipment has at least a first antenna and a second antenna for transmitting radio frequency signals between the user equipment and the base station. The base station has a plurality of antennas for transmitting radio frequency signals between the base station and user equipment. The user equipment further transmits a first training signal to the base station via the first antenna in the first period, and sends a second training signal to the base station via the second antenna as the first period. Has a processing device configured to transmit in a different second period. To accomplish this, the user equipment may include one transmission unit and may include a switch that selectively connects the transmission unit to either the first antenna or the second antenna. The processing device is further configured to receive the first downlink data from the base station via the first antenna and simultaneously receive the second downlink data from the base station via the second antenna. The Thus, the user equipment may comprise one, ie two receiving units for each antenna. The processing apparatus also determines a first signal quality parameter of the received first downlink data, and determines a second signal quality parameter of the received second downlink data. Then, based on the determined first and second signal quality parameters, the processing apparatus transmits uplink data to the base station via either the first antenna or the second antenna. In order to transmit the uplink data, the processing device may configure the above-described switch such that one transmission unit of the user equipment is connected to either the first antenna or the second antenna.

  According to an embodiment, the user equipment is configured to perform the method described above and the method of the embodiment described above, and thus has the advantages described above. The user equipment may comprise, for example, a mobile phone, a mobile computer, a personal digital assistant, a tablet computer.

  According to another embodiment, the base station may determine corresponding first and second quality parameters based on the received first and second training signals, from the user equipment to the base station. An antenna may be selected from among the first and second antennas of the user equipment for transmitting the uplink data. Accordingly, the base station may determine which channel is better by comparing the received training signals and determine the corresponding antenna for the incoming uplink data for use by the user equipment. May be.

  Although specific features described in the foregoing summary and in the following detailed description are described in connection with specific embodiments and aspects of the invention, the exemplary embodiments and aspects unless otherwise noted. It is understood that the features can be combined with each other.

The present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 shows an overview of a base station and user equipment according to an embodiment of the present invention. FIG. 2 shows schematic details of a user equipment according to an embodiment of the present invention. FIG. 3 shows a flowchart including method steps for transmitting data between a user equipment and a base station in a wireless network according to an embodiment of the present invention. FIG. 4 shows an overview of data transmission between a user equipment and a base station according to an embodiment of the present invention. FIG. 5 shows an overview of data transmission between a user equipment and a base station according to an embodiment of the present invention. FIG. 6 shows an overview of data transmission between a user equipment and a base station according to an embodiment of the present invention. FIG. 7 shows an overview of data transmission between a user equipment and a base station according to an embodiment of the present invention.

  In the following, exemplary embodiments of the invention will be described in more detail. Unless otherwise noted, it is understood that the features of the various exemplary embodiments described herein can be combined with each other. Like reference symbols in the various drawings indicate like or identical components. Any coupling between components or devices shown in the figures may be coupled directly or indirectly unless otherwise noted.

  FIG. 1 shows a user equipment 15 arranged in the environment 10 of the base station 11. The base station 11 includes a plurality of antennas 12 and associated transceivers 13. In FIG. 1, six antennas 12 and six transceivers 13 are shown for clarity. However, these are merely exemplary numbers, and the base station 11 may include 30 to 100 or more antenna arrays and associated transceivers arranged, for example, in a matrix or cylinder. User equipment 15 includes two antennas 16, 17. However, the user equipment 15 may include more antennas, for example three or four. The base station 11 further comprises a processing unit (PD) 14 connected to the transceiver 13 and adapted to constitute a transceiver 13 for transmitting radio frequency signals between the base station 11 and the user equipment 15. The multiple antennas 12 and transceiver 13 of the base station 11 allow the multi-input multi-output (MIMO) technique described above to be implemented for data transmission between the base station and each of the antennas 16 and 17 of the user equipment 15. May be used and configured. That is, the antenna 12 and the transceiver 13 of the base station 11 may be configured to provide two communication channels between the base station 11 and the user equipment 15 that are separated by spatial coding.

  FIG. 2 shows the user equipment 15 in more detail. The user equipment 15 comprises two antennas 16 and 17 connected via a switch 18 to a transceiver 20 including a first receiver 19 and a transmitter 21 and a second receiver 22. The user equipment 15 also includes a processing device (PD) 23 connected to a switch 18 that controls the switch. Under the control of the processing device 23, the switch 18 may connect the first antenna 16 to the first receiver 19 and connect the second antenna 17 to the second receiver 22, for example. May be selectively connected to either the first antenna 16 or the second antenna 17. Thus, the two receivers 19 and 22 may continuously receive signals via the antennas 16 and 17, and one of the antennas 16 and 17 receives a radio frequency signal from the transmitter or transmission unit 21. May be provided.

  In order to set up the two communication channels described above between the base station 11 and the user equipment 15, the transceiver 13 takes into account the spatial information of the antennas 16 and 17 of the user equipment 15 and provides a high transmission quality to the base station 11. Must be configured to provide. A radio frequency signal training signal or training sequence may be transmitted from each of the antennas 16, 17 of the user equipment 15 to the base station 11 to determine a set of configuration parameters for the transceiver 13. Based on the received training signal, corresponding configuration parameters for transceiver 13 may be determined at base station 11. However, if the user equipment 15 is moving, the configuration of the transceiver 13 must be updated to a new location to avoid degradation of transmission quality. Therefore, the training signals from the antennas 16 and 17 must be transmitted at regular intervals, for example, at the beginning of each frame transmitted between the base station 11 and the user equipment 15.

  Typical for use in a wireless communication network, such as an uplink part for transmitting data from the user equipment 15 to the base station 11 and a downlink part for transmitting data from the base station 11 to the user equipment 15 The transmission frame may include a header. The training signal described above may be transmitted to each antenna 16, 17 of the user equipment 15 in a separate time slot. To achieve this with only one transmission unit 21 of the user equipment 15, the method 30 shown in FIG. 3 may be utilized by the base station 11 and the user equipment 15.

  FIG. 3 shows steps 31 to 38 of the method 30. In step 31, the processing device 23 of the user equipment 15 connects the first antenna 16 to the transmission unit 21, and the first training signal is transmitted to the base via the first antenna 16, for example, in the header of the transmission frame. The switch 18 is configured to be transmitted to the station 11 in the first period or time slot. In step 32, the base station 11 determines a corresponding first configuration parameter for each antenna 12 of the base station 11 based on the first training signal received by the corresponding antenna 12. Next, the processing device 23 configures the switch 18 so that the transmission unit 21 is connected to the second antenna 17, and the second training signal is transmitted to the base station 11 via the second antenna 17 in step 33. Is done. The processing device 14 of the base station 11 determines a second configuration parameter corresponding to each antenna 12 of the base station 11 based on the second training signal received by the corresponding antenna (step 34). In step 35, the base station transmits the downlink data to the user equipment 15 via both channels. That is, the base station 11 transmits the first downlink data from the base station 11 to the user equipment 15 using the first configuration parameter for the antenna 12, and at the same time, the base station 11 The second downlink data is transmitted to the user equipment 15 using the parameters. Due to the spatial coding via the first configuration parameter and the second configuration parameter, the first downlink data is received with high quality at the first antenna 16 and the second downlink data is received at the second antenna 17. Received with high quality. In steps 36 and 37, the base station indicates the received quality at the first antenna via a first quality parameter and indicates the received quality at the second antenna via a second quality parameter. A corresponding quality parameter is determined for each of the data. Based on the determined first and second signal quality parameters, either first antenna 16 or second antenna 17 is selected for transmission of uplink data from user equipment 15 to base station 11 (Step 38).

  As described in the section related to the background of the present invention, the user equipment 15 may operate in either a diversity mode called rank 1 mode or a MIMO mode called rank 2 mode. In the diversity mode, the base station transmits the same data in the first downlink data and the second downlink data. That is, the same data is transmitted from the base station 11 to the user equipment 15 via two channels, and is received twice by the user equipment 15 via the first antenna 16 and the second antenna 17. If one of the channels is disturbed, for example by the user covering one of the antennas 16, 17 with the user's hand, the downlink data is still received at the user equipment 15. In the MIMO mode, the base station 11 transmits different downlink data, and thus the amount of transmission data is doubled.

  Data transmission between the user equipment 15 and the base station 11 described above is described in more detail below in an exemplary embodiment associated with FIGS. 4-7. In particular, the above-described step 38 of selecting an antenna for transmission of uplink data is described in more detail in various exemplary embodiments.

  In FIG. 4, a first embodiment is shown in which the selection of antennas used for uplink data transmission is performed at the user equipment 15 and the base station 11 is notified of the selection. In FIG. 4, two transmission frames 40 and 41 for each channel are shown. Each channel relates to spatially encoded communication between the base station 11 and each of the antennas 16, 17 of the user equipment 15. Data transmission on the first channel is identified with a postfix “1” and data communication over the second channel is identified with a postfix “2”. With spatial coding, the frame of the first channel may be transmitted simultaneously with the frame of the second channel. Thus, the horizontal direction of FIG. 4 indicates time, the first line of the box is associated with the first channel, and the second line of the box is associated with the second channel.

  Transmission starts with transmission of header information 50 of the first channel and header information 70 of the second channel. The heads of each channel are synchronized so that the time slots in the header may be used separately for each user equipment and each antenna of the user equipment. Thus, there is a dedicated time slot in the header 50 for transmission of the first training signal from the first antenna 16, and a dedicated time slot for transmitting the second training signal from the second antenna 17. There is. As described above, the processing device 23 configures the switch 18 so that the transmission unit 21 is connected to the first antenna 16 and the first training signal is transmitted in the header 50 as shown in FIG. Then, the processing device 23 configures the switch 18 so that the transmission unit 21 is connected to the second antenna 17 and the second training sequence is transmitted by the header 70 as shown in FIG. Next, the processing device 23 configures the switch 18 to connect the transmission unit 21 and the first antenna 16, and the first uplink data (UL1) 51 is transmitted from the user equipment 15 to the base station 11. The The first uplink data 51 includes information that notifies the base station which antenna is used for the next frame 41. In this case, for example, the user equipment 15 decides to select the second antenna 17 for the next transmission of uplink data based on the quality of the previously received (not shown) downlink data. May be. The base station 11 then transmits the first and second downlink data (DL1, DL2) 52, 72 to the user equipment 15 via both channels in a spatially encoded manner. The first and second downlink data may include the same data or different data depending on the transmission mode used, such as diversity mode or MIMO mode. The next frame 41 begins again with headers 53 and 73 for each channel containing first and second training signals that update the first and second configuration parameters for antenna 12. And as previously notified, the user equipment 15 connects the transmission unit 21 to the second antenna 17 and transmits uplink data (UL2) 74 to the base station via the second channel. Again, uplink data (UL2) 74 may include information for the base station which channel is used by user equipment 15 in the next frame (not shown). The channel or antenna used for the uplink data may be selected based on the quality parameters determined for the received first and second downlink data. For example, a first signal quality parameter for the first downlink data 52 may be determined, and a second signal quality parameter for the second downlink data 72 may be determined. The first and second signal quality parameters may be compared, and a channel with better quality may be selected to transmit the next uplink data. After the channel selected in the uplink data 74 is carried, that channel may be used in a further time frame (not shown). The base station 11 then transmits the first and second downlink data (DL1, DL2) 55, 75 simultaneously as described above, and the user equipment 15 receives the corresponding signal quality for future antenna reselection. The parameter may be determined.

  FIG. 5 shows a further embodiment of the method described in connection with FIG. In the embodiment shown in FIG. 5, user equipment 15 proposes one of antennas 16 or 17 for uplink data transmission, and base station 11 is provided with a closed communication loop for antenna selection. The request may be confirmed to As described in connection with FIG. 4, first and second training signals are transmitted in headers 50 and 70 of first frame 40. Based on the quality parameters determined for the downlink data received in the previous frame (not shown), the user equipment 15 proposes one of the antennas 16 and 17 for use in future uplink communications. For example, the user equipment 15 may propose to use the second antenna 17 in the future. This proposal is transmitted to the base station 11 via the uplink data (UL1) 51. Base station 11 then transmits downlink data (DL1, DL2) 52 and 72 to user equipment 15 on both channels, which may be used to determine future antenna selections. In the next frame 41, the user equipment still transmits uplink data (UL 1) 54 via the first antenna 16 unless a response to change the transmit antenna is received from the base station 11. In the downlink data (DL1, DL2) 55, 75 of the frame 41, the base station 11 may acknowledge the selection of the second antenna 17 proposed as the transmission antenna. Accordingly, the user equipment 15 transmits uplink data (UL2) 77 transmitted after the headers 56 and 76 in the next frame 42 to the base station 11 via the second antenna 17.

  FIG. 6 shows a further embodiment for antenna selection where the user equipment 15 may reselect without reporting to the base station 11 an antenna for transmitting uplink data to the base station. Therefore, the communication shown in FIG. 6 mainly corresponds to the communication shown in FIG. The only difference is that the user equipment 15 does not advertise the next channel used for the next uplink data in the uplink data (UL1 or UL2) 51 or 74. Therefore, the base station 11 must always listen to both channels and obtain uplink data from the channels for which uplink data is provided. Note that there is data on only one of the channels.

FIG. 7 shows a further embodiment for antenna selection where the base station 11 performs antenna selection and notifies the user equipment 15 accordingly. As described above, in the frame 40, the first and second training signals are transmitted from the user equipment 15 to the base station 11 in the headers 50 and 70. Next, the uplink data (UL1) 51 is transmitted from the user equipment 15 to the base station via the first channel. The base station then transmits downlink data (DL1, DL2) 52, 72 to the user equipment 15 on both channels. The user equipment 15 determines a first signal quality parameter of the first downlink data (DL1) 52 and a second signal quality parameter 72 of the second downlink data (DL2). In the next frame 41, after the first and second training signals are transmitted in the headers 53 and 73, the user equipment 15 determines the first and second signal qualities determined in the uplink data (UL1) 54. The parameter is transmitted to the base station 11 via the first antenna 16 on the first channel. The base station 11 further transmits to the user equipment 15 downlink data (DL1, DL2) 55 and 75 that may be used by the user equipment 15 to determine signal quality parameters. In the next frame 42, the training signal may again be transmitted in the headers 56 and 76, and the uplink data (UL1) 57 may be transmitted to the base station 11 via the first antenna 16. Based on the first and second quality parameters received in the frame 41, the base station 11 determines over time which communication channel provides better performance and therefore transmits uplink data in the future. The user equipment 15 may be instructed to use the second antenna 17 to do so. This information may be transmitted to the user equipment 15 in the downlink data (DL1, DL2) 58, 78 of the frame 42. Therefore, in the next frame 43, after the first and second training signals are transmitted in the headers 59, 79, the user equipment 15 configures the switch 18 to connect the transmission unit 21 to the second antenna 17. Uplink data (UL2) 80 is transmitted to the base station 11 via the second antenna 17. Finally, the base station 11 may transmit the downlink data (DL1, DL2) 61, 81 to the user equipment 15 via two channels simultaneously.

Claims (15)

A method for transmitting data between a user equipment and a base station in a wireless network, wherein the user equipment (15) transmits a radio frequency between the user equipment (15) and the base station (11). At least a first antenna (16) and a second antenna (17) for transmitting signals, wherein the base station (11) is located between the base station (11) and the user equipment (15). Comprising a plurality of antennas (12) for transmitting radio frequency signals at
Transmitting a first training signal in a first period from the user equipment (15) to the base station (11) via the first antenna (16);
For each antenna (12) of the subset of the plurality of antennas (12) of the base station (11), a corresponding first based on the first training signal received by the corresponding antenna (12) Determining the configuration parameters of
Transmitting a second training signal from the user equipment (15) to the base station (11) via the second antenna (17) in a second period different from the first period;
For each antenna (12) of the subset of the plurality of antennas (12) of the base station (11), a corresponding first number based on the second training signal received by the corresponding antenna (12). Determining two configuration parameters;
Using the first configuration parameter determined for the antenna (12) of the base station (11), the first downlink data (DL1) is transmitted from the base station (11) to the user equipment (15). And at the same time, using the second configuration parameter determined for the antenna (12) of the base station (11), the second downlink data (DL2) is transmitted to the base station. Transmitting from (11) to the user equipment (15);
Determining a first signal quality parameter of the first downlink data (DL1) received at the user equipment (15);
Determining a second signal quality parameter of the second downlink data (DL2) received at the user equipment (15);
Based on the determined first and second signal quality parameters, for transmission of uplink data (UL1, UL2) from the user equipment (15) to the base station (11), the user equipment ( And 15) selecting an antenna from the first and second antennas (16, 17).   The method of claim 1, wherein the step of selecting an antenna of the user equipment (15) is performed by the user equipment (15).   The method according to claim 2, further comprising notifying the selected antenna of the user equipment (15) from the user equipment (15) to the base station (11). Selecting an antenna of the user equipment (15),
Based on the determined first and second signal quality parameters, for transmission of uplink data (UL1, UL2) from the user equipment (15) to the base station (11), the user equipment ( Selecting a suitable antenna from among the first and second antennas (16, 17) of 15) by the user equipment (15);
Notifying the suitable antenna of the user equipment (15) from the user equipment (15) to the base station (11);
In order for the base station (11) to use the suitable antenna for transmission of the uplink data (UL1, UL2) from the user equipment (15) to the base station (11), the user equipment ( Responding to the user equipment (15) from the base station (11) to accept the preferred antenna of 15). Further comprising: transmitting the first and second signal quality parameters from the user equipment (15) to the base station (11), wherein the step of selecting an antenna of the user equipment (15) comprises the base station (11)
The method according to claim 1, comprising notifying the user equipment (15) of the selected antenna of the user equipment (15) from the base station (11).   The method according to any one of claims 1 to 5, wherein the first downlink data (DL1) is the same as the second downlink data (DL2).   The method according to any one of claims 1 to 5, wherein the first downlink data (DL1) is different from the second downlink data (DL2). The user equipment (15) is configured to selectively connect the transmission unit (21) and either the first antenna (16) or the second antenna (17) to the transmission unit (21). A switch (18),
Transmitting the first training signal comprises:
Connecting the transmission unit (21) to the first antenna (16) via the switch (18), and transmitting the second training signal,
The method according to any one of claims 1 to 7, comprising connecting the transmission unit (21) to the second antenna (17) via the switch (18). Determining the first signal quality parameter includes
Determining a bit error rate of the first downlink data (DL1);
Determining a received signal strength indication of the first downlink data (DL1);
Determining a signal-to-noise ratio of the first downlink data (DL1);
Including at least one of the groups
Determining the second signal quality parameter includes
Determining a bit error rate of the second downlink data (DL2);
Determining a received signal strength indication of the second downlink data (DL2);
Determining a signal to noise ratio of the second downlink data (DL2);
9. A method according to any one of claims 1 to 8, comprising at least one of the groups. The first and / or the second configuration parameter is:
Amplitude information,
Phase information,
A pair of parameters including amplitude information and associated phase information,
A plurality of said parameter pairs;
The method according to claim 1, comprising at least one of a group comprising: A wireless network base station,
A plurality of antennas (12) for transmitting radio frequency signals between the base station (11) and the user equipment (15), the user equipment (15) comprising the user equipment (15) and the base Comprising at least a first antenna (16) and a second antenna (17) for transmitting radio frequency signals to and from the station (11);
Furthermore, the base station
Receiving a first training signal transmitted from the user equipment (15) to the base station (11) via the first antenna (16) in a first period;
For each antenna (12) of the subset of the plurality of antennas (12) of the base station (11), a corresponding first based on the first training signal received by the corresponding antenna (12) Determine the configuration parameters of
Receiving a second training signal transmitted from the user equipment (15) to the base station (11) via the second antenna (17) in a second period different from the first period;
For each antenna (12) of the subset of the plurality of antennas (12) of the base station (11), a corresponding first number based on the second training signal received by the corresponding antenna (12). 2 configuration parameters are determined,
Using the first configuration parameter determined for the antenna (12) of the base station (11), the first downlink data (DL1) is transmitted from the base station (11) to the user equipment (15). ) And simultaneously using the second configuration parameter determined for the antenna (12) of the base station (11), the second downlink data (DL2) is transmitted to the base station (11). ) To the user equipment (15),
Receive uplink data (UL1) transmitted from the user equipment (15) via the first antenna (16) using the first configuration parameter, or from the user equipment (15) A base station comprising a processing unit (14) configured to receive uplink data (UL2) transmitted via the second antenna (17) using a second configuration parameter.   The base station according to claim 11, configured to perform the method according to any one of claims 1 to 10. A user equipment for a wireless network,
At least a first antenna (16) and a second antenna (17) for transmitting radio frequency signals between the user equipment (15) and the base station (11), and the base station (11) Comprises a plurality of antennas (12) for transmitting radio frequency signals between the base station (11) and the user equipment (15),
Transmitting a first training signal to the base station (11) via the first antenna (16) in a first period;
Transmitting a second training signal to the base station (11) via the second antenna (17) in a second period different from the first period;
The first downlink data (DL1) is received from the base station (11) via the first antenna (16) and simultaneously the second downlink data via the second antenna (17). (DL2) is received from the base station (11),
Determining a first signal quality parameter of the received first downlink data (DL1);
Determining a second signal quality parameter of the received second downlink data (DL2) and, based on the determined first and second signal quality parameters, the first antenna (16) or User equipment comprising a processing device (23) configured to transmit uplink data (UL1, UL2) to the base station (11) via any one of the second antennas (17).   14. User equipment according to claim 13, configured to perform the method according to any one of claims 1 to 10. 15. User equipment according to claim 13 or 14, comprising at least one of the group comprising a mobile phone, a mobile computer, a personal digital assistant, a tablet computer.

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